1. Field of the Disclosure
The present disclosure relates generally to drug reconstitution systems. More particularly, the present disclosure relates to a drug reconstitution system that reduces opportunities for user error.
2. Description of the Related Art
Certain drugs are preferably provided in powder or dry form (such as a lyophilized form), and require reconstitution prior to administration. Lyophilized drugs, for example, typically are supplied in a freeze-dried form that needs to be mixed with a diluent to reconstitute the substance into a form that is suitable for injection.
In addition, drugs may be provided as multipart systems which require mixing prior to administration. For example, one or more liquid components, such as flowable slurries, and one or more dry components, such as powdered or granular components, may be provided in separate containers which require mixing prior to administration.
There are a number of devices and methods for drug reconstitution. The most common method is to inject a diluent contained in a syringe into a vial containing a dry component of the drug. After shaking the vial to mix the dry and liquid components, the user withdraws the reconstituted drug fluid from the vial using a second syringe. The second syringe is then used to inject the reconstituted drug to a patient. This reconstitution process is labor intensive and introduces numerous opportunities for contamination of the needle tip or vial contents. In addition, there is also a danger that the patient or practitioner will accidently be pricked by the exposed needle. These steps are even more intimidating for a patient attempting to self-inject a reconstituted drug for the first time. Further, the needle of the injection syringe may be dulled by insertion through the vial stopper. A dulled needle is more likely to be painful and/or cause scarring when later inserted into a patient.
Numerous prior art devices seek to simplify the process of reconstituting a drug and injecting the reconstituted drug into a patient. For example, a common transfer assembly includes a syringe with a removable cartridge. The liquid component of the drug is forced from the cartridge to a vial for reconstitution with a dry component of the drug. The reconstituted fluid is then drawn back into the cartridge. The cartridge can then be removed from the transfer assembly and inserted into an injection syringe to deliver the fluid to the patient. This type of transfer device is generally larger and more complex than a typical syringe. Specifically, the device must include a structure to allow a user to easily remove the filled cartridge. In addition, the injection syringe must be compatible with the transfer device so that the cartridge removed from the transfer device can be inserted into the injection syringe.
Alternatively, an injector may be configured to permit mixing of dry and wet drug components prior to injection. To achieve mixing of substances in pen injectors, prior art devices have been developed that provide the wet component (e.g., liquid) and the dry component (e.g., powder) in separate chambers of a common container. The container is configured to permit the flow of the wet component to the dry component through a bypass channel to cause mixing thereof in preparing a solution for injection. However, these devices suffer several drawbacks. For example, these containers must be specifically configured for mixing and, typically, are more expensive to manufacture than conventional containers. In addition, these containers typically have a substantial amount of wasted dead space (e.g., volume of wasted dead space may be four to five times the volume of the accommodated substance). The excess wasted dead space results in larger-size containers, which may be less convenient to handle and more inaccurate for dosing purposes.
In view of the deficiencies of current methods and devices for drug reconstitution and injection, there is a need for a simpler device for reconstituting a drug and transferring the reconstituted drug to an injector for injection to a patient. Further, the system should reduce opportunities for user error by preventing exposure of needles before, during, and after use. Similarly, the system should reduce the opportunity for contamination by reducing the number of times that a needle must be inserted and removed from a drug vial or cartridge.